Sharp FO-1660M Operation Manual page 7

Regulatory information
This facsimile machine is only designed to operate in the country where approved.
Your Sharp FO-1660M Facsimile Transceiver is approved for connection to the Public
Switched Telephone Network (PSTN), it is also approved for connection via a Private
Branch Exchange (PBX), and can be used with either Loop Disconnect (LD) or Dual
Tone Multi-Frequency (DTMF) signalling.
Your facsimile machine is not suitable as an extension to some payphones or for use on
shared service lines.
REN
The Ringer Equivalence Number (REN) of your fax machine is 1.
The total number of instruments that can be connected to an exclusive line is determined
by adding the REN values of each instrument. The total should not exceed 4.0. A
telephone provided by BT is assumed to have a REN of 1 unless otherwise marked.
Satisfactory ringer operation can not be guaranteed in installations consisting of mixed
apparatus types, even if the REN value does not exceed 4.
Emergency services
Emergency services (999) can be called from this apparatus. Please display on the
telephone the number required to access that service, together with the number of the
telephone, using the label provided.
Private branch exchange (PBX) connection
Your facsimile machine is approved for connection to the Public Telephone Network
(PSTN) via compatible PBX systems. Consult your supplier for a list of suitable PBX
systems. It cannot be guaranteed that this facsimile machine will operate correctly under
all possible conditions of connection to compatible PBX systems.
This facsimile machine has been approved for use of the following facilities:
Simple telephone
Tone dialling (DTMF)
Loop disconnect (Pulse dialling)
Memory dialling
Loudspeaking (Call Progress Monitor)
On-hook dialling